Medicine and Health Sciences Commons^™

Peripheral Blood Epi-Signature Of Claes-Jensen Syndrome Enables Sensitive And Specific Identification Of Patients And Healthy Carriers With Pathogenic Mutations In Kdm5c, Laila C Schenkel, Erfan Aref-Eshghi, Cindy Skinner, Peter Ainsworth, Hanxin Lin, Guillaume Paré, David I Rodenhiser, Charles Schwartz, Bekim Sadikovic

Paediatrics Publications

Background

Claes-Jensen syndrome is an X-linked inherited intellectual disability caused by mutations in the

Results

Genome-wide DNA methylation analysis of 7 male patients affected with Claes-Jensen syndrome and 56 age- and sex-matched controls identified a specific DNA methylation defect (epi-signature) in the peripheral blood of these patients, including 1769 individual CpGs and 9 genomic regions. Six healthy female carriers showed less pronounced but distinctive changes in the same regions enabling their differentiation from both patients and controls. Highly specific computational model using the most significant methylation changes demonstrated 100% accuracy in differentiating patients, carriers, and controls in the training cohort, …

Identification Of A Novel Synaptic Protein, Tmtc3, Involved In Periventricular Nodular Heterotopia With Intellectual Disability And Epilepsy, Sali M K Farhan, Kevin C J Nixon, Michelle Everest, Tara N Edwards, Shirley Long, Dmitri Segal, Maria J Knip, Heleen H Arts, Rana Chakrabarti, Jian Wang, John F Robinson, Donald Lee, Seyed M Mirsattari, C Anthony Rupar, Victoria M Siu, Forge Canada Consortium, Michael O Poulter, Robert A Hegele, Jamie M Kramer

Paediatrics Publications

Defects in neuronal migration cause brain malformations, which are associated with intellectual disability (ID) and epilepsy. Using exome sequencing, we identified compound heterozygous variants (p.Arg71His and p. Leu729ThrfsTer6) in TMTC3, encoding transmembrane and tetratricopeptide repeat containing 3, in four siblings with nocturnal seizures and ID. Three of the four siblings have periventricular nodular heterotopia (PVNH), a common brain malformation caused by failure of neurons to migrate from the ventricular zone to the cortex. Expression analysis using patient-derived cells confirmed reduced TMTC3 transcript levels and loss of the TMTC3 protein compared to parental and control cells. As TMTC3 function is currently …

Mosaic Expression Of Atrx In The Mouse Central Nervous System Causes Memory Deficits, Renee J Tamming, Jennifer R Siu, Yan Jiang, Marco A M Prado, Frank Beier, Nathalie G Bérubé

Paediatrics Publications

The rapid modulation of chromatin organization is thought to play a crucial role in cognitive processes such as memory consolidation. This is supported in part by the dysregulation of many chromatin-remodelling proteins in neurodevelopmental and psychiatric disorders. A key example is ATRX, an X-linked gene commonly mutated in individuals with syndromic and nonsyndromic intellectual disability. The consequences of Atrx inactivation for learning and memory have been difficult to evaluate because of the early lethality of hemizygous-null animals. In this study, we evaluated the outcome of brain-specific Atrx deletion in heterozygous female mice. These mice exhibit a mosaic pattern of ATRX …